Steam generator



April 12 1927.

C. DUQUENN E STEAM GENERATOR Filed July 6. 1926 Q anvemtoz Qbtovm Patented Apr. 12, 1927.

v UNITED STATES TCAMILLE DUQUENNE, or PARIS, FRANCE.

STEAM, GENERATOR.

Application filed July 6, 1926, Serial No. 120,719, and in Germany October 13, 1924.

Steam generators are known in which the vaporizing elements are constituted by vertical or Substantially vertical straight tubes the upper and lower ends of which are connected to headers in communication with the shell of the generator and with the waterreturn collector respectively, the said shell and collector being in communication with one another through the medium of downcomers.

Great difficulties arise when a generator of this type is to be worked at particularly high pressure (as high as 200 kilograms per square centimetre for example) owing to a considerable drop in the difference in density between steam and water. The steam and water forming the mixture flowing from the vaporization elements into the upper header or headers are very difiicult to separate, with the result that extensive priming takes place in the shell of the generator, the said shell being simultaneously a water and steam reservoir, the surface of separation of the mixture and its path of travel being relatively small.

One object of my invention is to obviate this disadvantage by separating steam from water to a particularly high degree. A fur ther object is to separate the store of steam entirely from that of water and to secure a circulation of steam andwater which is livelier and more efiicient, with the consequence that the difference in density between the steam and water mixture issuing from the vaporizing elements and the water filling the water-return pipes is more marked.

With these objects in view, my invention essentially consists in the special combination and arrangement of parts as hereinafter fully described and pointed out in the appended claim. I

A constructional example of a steam genorator according to my invention is illustrated in the accompanying drawings in which:

Fig. 1 is a vertical section of the generator and i v Fig. 2 is a horizontal section thereof.

Referring more particularly to Figure 1, the steam generator has the usual masonry work 1 to form the furnace 2 at the rear of which are disposed vaporizing elements each comprising a number of vertical or substantially vertical tubes 3 connected in groups to headers 4 and 5. 7

According to my invention the upper headers 4 are not directly connected, in the usual way, to a single upper shell forming a water and steam reservoir, but are. c0nnected with the aid of joints 6 to one end of juxtaposed longitudinal cylindrical nicmbers 7 provided at the other end with a union member 8 whereby they are connected to an upper transverse chamber 9 forming a steam shell, and with a further union 10 whereby they are connected to a lower transverse chamber 11 forming a water reservoir. The ends of the chamber 11 are connected to a lower collector 13 by inclined downcomers 12 disposed externally to the masonry of the generator, the said collector being con nected in the usual way with the lower headers 5 of the vaporization elements by pipes 14 and union 15.

The steam generator according to my in vention works as follows. The water in the transverse chamber 11 is fed through the outer downcomers 12 to the collector 13, rises in the vertical tubes 3 heated by the furnace and is converted therein into an emulsion of water and steam supplied through the upper headers 4: to the longitudinal cylinders 7, two in number, in the construction shown, for four vaporizing elements each comprising a number of vertical tubes. The water flows at the forward end of the longitudinal cylinders 7 into the lower transverse chamber 11 whence it is returned to the circuit. Steam flows into the upper transverse chamber 9 in which it is stored to the exclusion of water.

Thelongitudinal cylinders 7 supported at one end on a rail 16, are mounted in practice so that they are afforded free endwise expansion. A steam generator constructed in accordance with my invention provides unusual and exceptionally good circumstances for causing a complete separation of the steam and water generated in the vaporizing tubes. This exceptional separation is caused and aided by the fact that the inlet to the longitudinal cylinders 7 is above the normal level of the water, shown by the dotted lines ww in Fig. 1, andby the fact that these longitudinal cylinders are of consider- .able length, thereby creating a long passage between the vaporizing tubes and the steam chamber thereby giving a longer period of time for the accomplishment of the separation,

What I claim is:

In a steam generator, in combination a lnri'iace, waymrizing elements comprising substantially vertical tubes located'in the path of the combustion gases from said furnace; upper and lower headers to WlliCllftl'lE said vaporizing elements are connected, horizontal. longitudinal cylindrical members", each of said cylnnh-Ecal members extending both above and belowthe normal water line connected to the upper headers of the vaporiw ing; elenients, the said members receiving the \vholeoil the emand "steam mixtnre prioduced in the vaporizing elements, a steam chamber erra'niged traneversally above the CAM'ILLE .eU UENNn. 

